Department of Neuropsychiatry, Fukushima Medical University, Hikarigaoka 1, Fukushima, Japan.
Department of Neuropsychiatry, Fukushima Medical University, Hikarigaoka 1, Fukushima, Japan.
Biol Psychol. 2020 Mar;151:107848. doi: 10.1016/j.biopsycho.2020.107848. Epub 2020 Jan 22.
Both stream segregation and temporal integration are considered important for auditory scene analysis in the brain. Several previous studies have indicated that stream segregation may precede temporal integration when both processes are required. In the present study, we utilized mismatch negativity (MMN)-which reflects automatic change detection-to systematically estimate the threshold of the frequency difference at which stream segregation occurs prior to temporal integration when these functions occur together during a state of inattention. Electroencephalography (EEG) data were recorded from 22 healthy Japanese men presented with six blocks of alternating high pure tones (high tones) and low pure tones (low tones). Only high tones were omitted with 5 % probability in all blocks. Our results indicated that stream segregation should cancel temporal integration of close sounds, as indicated by omission-MMN elicitation, when the frequency difference is 1000 Hz or larger.
音流分离和时间整合都被认为对大脑中的听觉场景分析很重要。几项先前的研究表明，当这两个过程都需要时，音流分离可能先于时间整合。在本研究中，我们利用失匹配负波（MMN）——反映自动变化检测——来系统地估计在不注意状态下这两个功能同时发生时，音流分离先于时间整合出现的频率差阈值。我们对 22 名健康的日本男性进行了脑电图（EEG）记录，给他们呈现了 6 组高频纯音（高音）和低频纯音（低音）的交替刺激。所有组中高音都以 5%的概率被随机省略。结果表明，当频率差为 1000Hz 或更大时，音流分离应该会消除近距离声音的时间整合，这可以通过省略 MMN 的诱发出。
